A chronic diabetic rat-model has been established which stimulates the human diabetic state better than the earlier acute diabetic models. Insulin-lack leads to a variety of alterations in intestinal calcium absorption, vitamin D metabolism and bone turnover. Total cellular RNA isolated from normal and rachitic rat intestine was also translated in a mRNA dependent-cell free system derived from wheat germ. One of the polypeptides synthesized has been identified as the intestinal CaBP. Estimates of CaBP mRNA abundance based on translational activity revealed that the vitamin D dependent mRNA represented less that 0.5% of the transcribed enterocyte mRNA population in normal intestinal mucosa.